The instant invention relates to liquid discharge systems and more particularly to a nozzle for discharging a liquid, such as a fire-retardent fluid, throughout a relatively narrow, elongated spray pattern.
Generally, the heretofore available discharge nozzles for use in fire-protection sprinkler systems have fallen into two main categories: closed nozzles with heat sensitive elements which are individually responsive to abnormally high-temperature conditions and open nozzles which only discharge liquid when an automatic control valve has been operated by an independent firedetection device. A variety of different liquid spray nozzles are included in these two general categories and have been heretofore available to meet the needs of various commercial and/or residential applications. Most of the heretofore-known liquid discharge nozzles have been operative for producing substantially circular liquid discharge patterns, and it has been found that nozzles of this type are satisfactory for many applications. These nozzles have been mainly used in fire protection systems of the type which comprise a plurality of nozzles which are disposed in a predetermined array so that the peripheral portions of the spray patterns of adjacent nozzles overlap slightly when liquid is discharged from them. Systems of this type have been effective for most fire-protection applications, although they have been somewhat inefficient in certain applications where the configurations of their spray patterns don't match the configurations of the areas to be protected.
A particular problem is presented when it is necessary to provide a fire-protection system for distributing liquid relatively uniformly throughout an elongated, relatively narrow coverage area. This problem is encountered in a number of industrial fire-protection system applications, such as open-nozzle systems for protecting relatively slender objects, such as long coal conveyors, long cylindrical petrochemical tanks, petroleum tank cars, electrical cable trays, and structural beams. Generally, several types of liquid discharge nozzles have been used for applications of this type, although they have not been highly efficient. For example, one scheme of sprinkler system which has been used for protecting relatively long slender objects comprises a plurality of conventional nozzles of the type which discharge liquid over a relatively short distance in either a conical or an umbrella shaped pattern, and which are positioned in generally aligned spaced relation. In order to produce a spray pattern which can provide adequate coverage for an elongated, relatively narrow area, the adjacent spray nozzles of a system of this type are directed generally perpendicular with respect to the designated coverage area and they must be positioned in relatively closely spaced relation so that the spray patterns thereof overlap to produce the desired combined spray pattern. A fire-protection system of this type requires a substantially greater than normal quantity of nozzles in order to produce the desired density of fire-retardent fluid coverage over the designated area for adequate fire protection. Hence, a greater than normal amount of piping is required for a system of this type, and much of the piping must be oversized to accommodate water flow rates which are higher than normal in order to assure that adequate quantities of liquid will be discharged. A second scheme which has been used for protecting relatively long slender objects comprises a plurality of conical spray nozzles of the type which discharge liquid over a relatively long distance and which are positioned in spaced, generally aligned relation, but which are directed generally longitudinally with respect to the desired coverage area. Systems of this type have also required substantial spray pattern overlapping in order to provide the desired coverage, so that they also have required greater than normal quantities of nozzles per unit area, and hence the piping for these systems has also required larger than normal pipe sizes. In both the first and second schemes described above, the source of the fire retardent fluid must also have a greater than normal flow capacity.
The problem of providing an effective fire protection system for a generally rectangular area has been addressed by the inventions disclosed in the U.S. patents to LEWIS U.S. Pat. Nos. 868,459; MOWRY 1,288,123; TYDEN 2,101,694; KENDALL 2,135,138; and VORKAPICH 3,880,239, these patents representing the closest prior art to the instant invention of which the applicant is aware. These references teach a variety of different discharge nozzle constructions which are intended to produce various different noncircular spray patterns. However, they do not teach a discharge nozzle which provides an effective, substantially uniform liquid spray pattern for covering a relatively narrow, elongated area. They also do not teach a spray nozzle having the specific structural features of the spray nozzle of the instant invention, and hence for these reasons references are believed to be of only general interest.
The instant invention provides a novel spray nozzle which effectively provides an elongated, relatively narrow spray pattern which is substantially uniform over its entire area of coverage. The nozzle of the instant invention comprises a deflector having an elongated central portion and a pair of side portions which diverge angularly from the opposite side edges of the central portion and which each have a plurality of tines formed in the terminal portions thereof, and a frame for mounting the deflector adjacent a liquid discharge outlet so that when liquid is discharged from the outlet it impinges on the inner surface of the deflector in the central portion thereof and it is deflected outwardly along the inner surfaces of the side portions of the deflector. Preferably the deflector is of a generally V-shaped configuration with a curved central or apex portion, and the deflector and the frame are positioned so that when liquid is discharged from a discharge outlet, it impinges on the deflector in the area thereof where the deflector is attached to the frame. Further, in the preferred embodiment, a generally elliptically shaped boss is provided on the inner side of the deflector in the area thereof where the deflector is attached to the frame. A boss is also provided on the frame at the point where deflector is interconnected thereto. The two bosses are configured so that they cooperate, with the deflector boss being the more important, to at least partially redirect liquid from the discharge outlet so that the liquid passes generally outwardly in all directions from the axis of the liquid discharge and along the inner surfaces of the deflector. In addition, in the preferred embodiment of the nozzle, the tines which are located along the terminal portions of the side portions of the deflector are defined by slots which extend generally inwardly and towards the point where the deflector is attached to the frame so that they are generally aligned with the natural flow of liquid on the inner side of the deflector, and the tines in the central portions of the longitudinal peripheries of the deflector are bent inwardly slightly.
It has been found that as a result of the novel structural features of the spray nozzle of the instant invention it is operative for providing a relatively uniform distribution of liquid over an elongated, relatively narrow area. The boss on the inner side of the deflector and the mounting boss formed as part of the upper portion of the mounting frame cooperate to at least partially redirect liquid from the discharge outlet so that when it passes along the inner surfaces of the deflector a relatively uniform distribution liquid is achieved through the central portion of the elongated spray pattern. The combination of the slots and tines located along the longitudinal side edges of the deflector helps to spread the flow uniformly throughout the regions adjacent to the longitudinal peripheries of the relatively narrow spray pattern and the included angle between the side portions generally defines the central width of the spray pattern. The combination of the tines and the slots tends to break up the flow of liquid as it passes along the inner surfaces of the deflector so that it is randomly and relatively uniformly distributed throughout the regions adjacent to the longitudinal peripheries of the spray pattern. Further, the slots which define the tines are positioned so that they extend generally outwardly relative to the bosses in the central portion of the nozzle and as a result they are generally aligned with the natural flow of liquid as it moves outwardly on the inner surfaces of the deflector. Accordingly, all of these structural features cooperate to provide a nozzle which discharges liquid in an elongated, relatively narrow spray pattern and which provides a relatively uniform distribution of liquid throughout its coverage area.
It is, therefore, a primary object of the instant invention to provide an effective liquid spray nozzle for producing an elongated, relatively narrow, substantially uniform spray pattern.
Another object of the instant invention is to provide a spray nozzle which can be effectively used in fire-protection systems for relatively long slender objects.
Another object of the instant invention is to reduce the installation cost of fire-protection systems for relatively long, slender objects by discharging almost all of the available liquid over the designated coverage area.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.